R33 Missfire On Cruise

[ZacZerbst]

i have tested the vehicle on a gas bench and everything is good has a lambda reading of 1.02. and all the other gas levels are within specs. i have recently replaced the coils, spark plugs, fuel filter and o2 sensor . i have also cleaned the air fuelter and afm.

the vehicle runs fine at idle but once you start crusing along anywhere between 80 and 120 with the engine at operating temperature the car se

ems to jolt as if a really bad miss is present.

i have also noticed that the power light flashes on start up. after running diagnostis the lock up solenoid signal is missing or faulty or something cant remember exactly what it means. could this have something to do with it?

the car is a 1993 nissan skyline r33 gts with an auto transmission.

any idea would be appreciated

[GTRSOL]

Hi mate i have a r32 gtr doing the same thing however mine happens very seldem.

happens when i come off boost at lower revs quickly and also cruising, have had fuel filter, pods, and sparks done.

[SargeRX8]

You sure its misfire and not lean pop? They kind of sound and feel the same... Can't imagine misfire under low load and no miss under wot...

[89CAL]

Is the engine missing or is it the gearbox making it feel like the engine is missing? Need to know if its a gearbox or engine problem

[boostn0199]

Id be checking the CAS if its a lean popping during cruising.

[89CAL]

i have tested the vehicle on a gas bench and everything is good has a lambda reading of 1.02. and all the other gas levels are within specs. i have recently replaced the coils, spark plugs, fuel filter and o2 sensor . i have also cleaned the air fuelter and afm.

the vehicle runs fine at idle but once you start crusing along anywhere between 80 and 120 with the engine at operating temperature the car se

ems to jolt as if a really bad miss is present.

i have also noticed that the power light flashes on start up. after running diagnostis the lock up solenoid signal is missing or faulty or something cant remember exactly what it means. could this have something to do with it?

the car is a 1993 nissan skyline r33 gts with an auto transmission.

any idea would be appreciated

This is why I ask is it actually the engine missing or the transmission slipping/dropping out

Do the revs drop when this happens or do they stay the same/rise?

[AngryRB]

Id be checking the CAS if its a lean popping during cruising.

[/quote

is it while cruising or while comming off the throttle? cause mine has started doing that

[SargeRX8]

is it while cruising or while comming off the throttle? cause mine has started doing that

When you come off throttle and in gear the car should just hummm to a lower speed then it will burble when the rpm is too low for the gear. My car was running perfectly during cruise, now it lean pops its arse off ONLY during cruising. Full throttle, medium throttle etc is fine. Touching the throttle lightly to maintain a steady cruise speed sees lean popping.

[ZacZerbst]

the revs drop off by about 500rpm. im not sure if its the gearbox or engine was hoping someone could help me out there. is there anyway of checking for a lean pop while driving.

[SargeRX8]

500rpm drop is fair big... If it was your gearbox it would go up rather than down... Lean popping will cause your engines rpm to splutter around. If you have a big exhaust, hold the rpm with the window shut and you should hear the thud of the lean pop. My car is like. pop..........pop.....pop pop pop etc and revs bounce around and the car will jitter. Misfire sounds like a machine gun, kind of like lean pop but VERY rapid.

Only way is by sound and by AFR plots. This is misfire

[ZacZerbst]

its not a straight 500 drop. alot of the time i get multiples in a row adding up to 500 rpm. ill try your check next time it starts happening. what is your sugested fix for a lean pop?

[SargeRX8]

its not a straight 500 drop. alot of the time i get multiples in a row adding up to 500 rpm. ill try your check next time it starts happening. what is your sugested fix for a lean pop?

I fixed my lean pop today, required a touch up in some cells in the tune. If you are running after market ECU, injectors and what not then it is very likely you will suffer from lean pop. Its common on Skylines and they require a little more fuel then stoich to run smooth.